[libvirt PATCH 7/7] ci: integration.sh: Define the SCRATCH_DIR variable for local execution

[Erik Skultety]

On Mon, Jan 23, 2023 at 12:02:44PM +0000, Daniel P. Berrangé wrote:
> On Mon, Jan 23, 2023 at 10:50:31AM +0100, Erik Skultety wrote:
> > On Mon, Jan 23, 2023 at 09:41:10AM +0100, Martin Kletzander wrote:
> > > On Fri, Jan 20, 2023 at 04:06:03PM +0100, Erik Skultety wrote:
> > > > Running outside of GitLab will likely not have the variable set and
> > > > hence the execution would fail.
> > > > 
> > > > Signed-off-by: Erik Skultety <eskultet at redhat.com>
> > > > ---
> > > > ci/integration.sh | 8 ++++++++
> > > > 1 file changed, 8 insertions(+)
> > > > 
> > > > diff --git a/ci/integration.sh b/ci/integration.sh
> > > > index 41326d6e40..ac04c46d8e 100644
> > > > --- a/ci/integration.sh
> > > > +++ b/ci/integration.sh
> > > > @@ -37,6 +37,14 @@ virsh net-start default &>/dev/null || true
> > > > # END AS ROOT
> > > > exit
> > > > 
> > > > +# If we're running outside of GitLab, this variable will likely not exist, so
> > > > +# we need to define it and create the scratch directory
> > > > +if [ -z "$SCRATCH_DIR" ]
> > > > +then
> > > > +    SCRATCH_DIR="/tmp/scratch"
> > > > +    mkdir "$SCRATCH_DIR" 2>/dev/null
> > > 
> > > This could fail if someone has this directory already.  Which is a good
> > > thing as otherwise it could override some of it.  But wouldn't it be
> > > nicer to use mktemp -d and print the result?
> > 
> > Although an option, the main motivation here to remain consistent with how it
> > works in GitLab. Since we define SCRATCH_DIR under the 'vars' section, IIRC you
> > can only use a scalar value, not a command (if we can, I retract my argument)
> > and hence we'd have to export and define the variable under each script,
> > before_script, after_script sections.
> > 
> > So, I preferred consistency here, since I wouldn't  realistically expect an
> > engineer to have /tmp/scratch prior to executing script given the main
> > motivation here is to quickly get a throwaway test machine to run the script
> > and THEN debug if the tests fail. So, while I agree you're right here, I don't
> > think it's a likely scenario.
> 
> I'm wondering why I put it at /tmp/scratch in the first place when we
> started using gitlab, and struggling to come up with a justification.

I think I may have found the answer to ^this - variables can only be static
strings, so $PWD/vroot would not be an option in such case. The obvious benefit
is that the variables are inherited to all jobs which extend a template, so
even if we currently use SCRATCH_DIR in a single YAML file only, I'd like to
keep it that way.

> 
> In fact I'm not entirely convinced we really need a SCRATCH_DIR env
> variable at all, since AFAICT, we only use it one place for creating
> $VROOT.
> 
> In terms of standalone reproduction of build env, it would be saner
> to use VOORT=$CWD/vroot, which I think would probably work under
> GitLab ok too, and do away with SCRATCH_DIR.

Like I mentioned in my previous response, seems like we'd only rename the
variable and even had to re-define it in all (.*_)?script sections along with
all inherited templates.
So, to keep being consistent with other libvirt projects where I believe we
still use SCRATCH_DIR in this form. Let's just fix the ramdisk mount issue and
move it to /var/tmp - it's a static path, everyone has access there (EUID
depends on how the runner was configured), and it's persistent storage

Regards,
Erik